include/wait.h

   1 /* Define how to access the int that the wait system call stores.
   2    This has been compatible in all Unix systems since time immemorial,
   3    but various well-meaning people have defined various different
   4    words for the same old bits in the same old int (sometimes claimed
   5    to be a struct).  We just know it's an int and we use these macros
   6    to access the bits.  */
   7
   8 /* The following macros are defined equivalently to their definitions
   9    in POSIX.1.  We fail to define WNOHANG and WUNTRACED, which POSIX.1
  10    <sys/wait.h> defines, since our code does not use waitpid().  We
  11    also fail to declare wait() and waitpid().  */
  12
  13 #define WIFEXITED(w)    (((w)&0377) == 0)
  14 #define WIFSIGNALED(w)  (((w)&0377) != 0177 && ((w)&~0377) == 0)
  15 #ifdef IBM6000
  16
  17 /* Unfortunately, the above comment (about being compatible in all Unix
  18    systems) is not quite correct for AIX, sigh.  And AIX 3.2 can generate
  19    status words like 0x57c (sigtrap received after load), and gdb would
  20    choke on it. */
  21
  22 #define WIFSTOPPED(w)   ((w)&0x40)
  23
  24 #else
  25 #define WIFSTOPPED(w)   (((w)&0377) == 0177)
  26 #endif
  27
  28 #define WEXITSTATUS(w)  ((w) >> 8)      /* same as WRETCODE */
  29 #define WTERMSIG(w)     ((w) & 0177)
  30 #define WSTOPSIG(w)     ((w) >> 8)
  31
  32 /* These are not defined in POSIX, but are used by our programs.  */
  33
  34 #define WAITTYPE        int
  35
  36 #define WCOREDUMP(w)    (((w)&0200) != 0)
  37 #define WSETEXIT(w,status) ((w) = (0 | ((status) << 8)))
  38 #define WSETSTOP(w,sig)    ((w) = (0177 | ((sig) << 8)))